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chonny
Sep22-03, 09:57 PM
Please help me...I've been struggling for a long time over this following problem... [g)]

Some cockroaches can run as fast as 1.5 m/s. Suppose that two cockroaches are separated by a distance of 60 cm and that they begin to run toward each other at the same moment. Both insects have constant acceleration until they meet. The first cockroach has an acceleration of 0.20 m/s^2 in one direction and the second one has an acceleration of 0.12 m/s^2 in the opposite direction. How much time passes before the two insects bump into each other?


Please give me the answer and the steps leading to the answer as soon as possible...I am most grateful [;)]

If not...I will kill myself [:((]

MathematicalPhysicist
Sep23-03, 12:00 AM
a_1=0.2
a_2=0.12
v_01=v_02=0
x=x_0+v_0*t+at^2/2
x_1=0+0+a_1*t^2/2=0.2*t^2/2
x_2=0+0+a_2*t^2/2=0.12*t^2/2
x_1+x_2=60
0.2*t^2/2+0.12*t^2/2=60
t=19.36 sec


p.s
dont kill yourself [:)]

chonny
Sep23-03, 07:31 AM
thank you ...*puts down shotgun* [:))]